Omron CJ1G-CPUxx, Instructions Manual

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620
Table Data Processing Instructions
Section 3-17
LIFO(634)
Reads the last (most recent) word of data that was stored in the stack. Decre-
ments the pointer by one and reads the data at this address (the most recent
data stored in the stack). The read data will not be cleared.
SREAD(639)
Reads the data from the specified data element in the stack. The offset value
indicates the location of the desired word (the number of words before the cur-
rent pointer position).
Stack
Pointer
Stack
Pointer
Data region Data region
A is the last word
stored in the stack.
Decrements the pointer by one
and reads content of A.
A
B
A
B
A
:
A
B
C
:
A
B
C
Data region
Pointer
Pointer
(Unchanged)
Last word of
data in stack
Stack
Data region
Data in pointer position - n
(n=3 in this example.)
Stack
Pointer to last
word in stack
Pointer
Reads data from pointer
position - n.
(n=3 in this example.)
-n
(n=3)